commit b01e955ab061562aeafed78f87ba7b456f65544b
parent d915a43dd0447d3d1bdd55351a8d3f06bbb3fbcf
Author: Anders Damsgaard <anders@adamsgaard.dk>
Date: Thu, 26 Sep 2019 20:29:26 +0200
Add new figures and pulse tests
Diffstat:
6 files changed, 72 insertions(+), 7 deletions(-)
diff --git a/BIBnew.bib b/BIBnew.bib
@@ -9050,3 +9050,38 @@ Winton and A. T. Wittenberg and F. Zeng and R. Zhang and J. P. Dunne},
title = {In situ measurements of the resistivity of Antarctic sea ice},
journal = {Cold Regions Sci. Technology}
}
+
+@article{Hart2019,
+ doi = {10.1038/s41467-019-09547-6},
+ year = 2019,
+ month = {apr},
+ publisher = {Springer Nature},
+ volume = {10},
+ number = {1},
+ author = {J. K. Hart and K. Martinez and P. J. Basford and A. I. Clayton and B. A. Robson and D. S. Young},
+ title = {Surface melt driven summer diurnal and winter multi-day stick-slip motion and till sedimentology},
+ journal = {Nature Commun.}
+}
+@article{Bougamont2019,
+ doi = {10.1029/2018jf004707},
+ year = 2019,
+ month = {jan},
+ publisher = {American Geophysical Union ({AGU})},
+ volume = {124},
+ number = {1},
+ pages = {80--96},
+ author = {M. Bougamont and P. Christoffersen and I. Nias and D. G. Vaughan and A. M. Smith and A. Brisbourne},
+ title = {Contrasting Hydrological Controls on Bed Properties During the Acceleration of Pine Island Glacier, West Antarctica},
+ journal = {J. Geophys. Res.: Earth Surf.}
+}
+@article{Melanson2013,
+ doi = {10.1016/j.quascirev.2013.02.017},
+ year = 2013,
+ month = {may},
+ publisher = {Elsevier {BV}},
+ volume = {68},
+ pages = {154--174},
+ author = {A. Melanson and T. Bell and L. Tarasov},
+ title = {Numerical modelling of subglacial erosion and sediment transport and its application to the North American ice sheets over the Last Glacial cycle},
+ journal = {Quat. Sci. Rev.}
+}
diff --git a/continuum-granular-manuscript1.tex b/continuum-granular-manuscript1.tex
@@ -49,25 +49,47 @@ We show that past pulses in water pressure can transfer shear away from the ice-
\section{Introduction}%
\label{sec:introduction}
-Subglacial sediment deformation is in many settings a constituent of primary importance to glacier flow \citep[e.g.][]{Boulton1974, Engelhardt1990, Fischer1994, Truffer2006}.
-The mechanical behavior of the sediment is long debated \citep[e.g.][]{Alley1986, Boulton1987, Kamb1991, Iverson1995, Hooke1997, Tulaczyk2001, Fowler2003, Iverson2010}.
-The earliest applied till rheologies were viscous in nature, allowing the formulation of analytical solutions to the coupled ice-till problem \citep[e.g.][]{Walder1994, Hindmarsh1999, Fowler2000}, and a glacier sliding law similar to hard-bed sliding laws without cavitation \citep[e.g.][]{Budd1979}.
+Subglacial sediment deformation is in many settings of primary importance to glacier flow \citep[e.g.][]{Boulton1974, Engelhardt1990, Fischer1994, Truffer2006}.
+The mechanical behavior of the sediment is long debated \citep[e.g.][]{Alley1986, Boulton1987, Kamb1991, Iverson1995, Hindmarsh1997, Hooke1997, Fowler2003, Iverson2010, Hart2011}.
+Early on, till was assumed to be viscous \citep{Boulton1987} which allowed the formulation of analytical solutions to the coupled ice-till problem \citep[e.g.][]{Walder1994, Hindmarsh1999, Fowler2000}.
+Resultant glacier sliding laws are similar to hard-bed sliding laws without cavitation \citep[e.g.][]{Budd1979}.
+However, laboratory experiments on tills \citep[e.g.][]{Kamb1991, Iverson1998, Tulaczyk2000, Rathbun2008, Iverson2010, Iverson2015}
+and field observations \citep[e.g.][]{Iverson1995, Hooke1997, Tulaczyk2006}
+have concluded that till strength is nearly rate-independent, adhering to Mohr-Coulomb plasticity.
+
+\citet{Damsgaard2016} showed that creep before failure is rate dependent,
+
+\citet{Hart2011} argued that the rheology is dependent on water pressure.
+
+% remote-sensing inversion and modeling
+% Gudmundsson, Robel, Minchew, Winberry2011, Walker2013, Thompson2014, Rosier2015, Ritz2015, Bindschadler2003
-% Iverson1998
-% Tulaczyk2001, Tulaczyk2006
% Hart2017, Hart2019
% Damsgaard2013
% Iverson2015
% Damsgaard2016
+% Joughin2010
+
% Tsai, Schoof
+The \emph{undrained plastic-bed} model by \citet{Tulaczyk2000b} uses the relationship between sediment void-ratio, effective normal stress, and shear stress to link hydraulics with till strength.
+This parameterization has been included in ice sheet models, successfully reproducing transient flow dynamics \citep{Bougamont2011, vanDerWel2013, Gillet-Chaulet2016, Bougamont2019}.
+
+\citet{Schoof2010} produced a reguralized form of the Coulomb friction sliding law, making it feasible to simulate sliding over plastic tills in ice-sheet models.
+However,
+
+
+\citet{Iverson2001} demonstrated that perturbations in effective stress at depth can distribute deformation away from the ice-bed interface.
+
+
% Tarasov?
+\citep{Melanson2013}.
+
+
-% remote-sensing inversion and modeling
-% Gudmundsson, Robel, Minchew, Winberry2011, Walker2013, Thompson2014, Rosier2015, Ritz2015, Bindschadler2003
% Minchew2019
@@ -348,6 +370,14 @@ The shear velocities during the first cycle ($t<1$ d) is slightly different from
\end{center}
\end{figure}
+\begin{figure}[htbp]
+ \begin{center}
+ \includegraphics[width=0.49\textwidth]{experiments/pulse-triangle-fig4b.pdf}
+ \includegraphics[width=0.49\textwidth]{experiments/pulse-square-fig4b.pdf}
+ \caption{\label{fig:pulse}%
+ }
+ \end{center}
+\end{figure}
\begin{figure*}[htbp]
\begin{center}
diff --git a/experiments/fig5.pdf b/experiments/fig5.pdf
Binary files differ.
diff --git a/experiments/fig5b.pdf b/experiments/fig5b.pdf
Binary files differ.
diff --git a/experiments/pulse-square-fig4b.pdf b/experiments/pulse-square-fig4b.pdf
Binary files differ.
diff --git a/experiments/pulse-triangle-fig4b.pdf b/experiments/pulse-triangle-fig4b.pdf
Binary files differ.